You can have foreign investment and affordable housing. Don't blame the whole housing crisis on foreigners -- we created the affordable housing crisis ourselves. Foreign investment makes us better off, not worse off. Maybe your rent goes up $25 because of increased housing demand from foreign buyers, but then your city is now benefiting from tax revenue from these foreigners and providing you with more services that you benefit from -- let's say, for example, they hire more teachers to deliver a higher quality education at the same price for your children. Now these new teachers need to look presentable for their students so now maybe the local hair dresser is getting more business, and so she decides to expand into the neighboring space and hires you to manage construction...
What i'm getting at here is that more value and economic activity in a community flows around and benefits everyone in a lot of ways. It's somewhat ridiculous to say it would be a good thing to watch the price of US assets fall when foreign investment is probably not even in the top 3 reasons for the current housing situation in the US. Even if housing becomes slightly more affordable, you are losing the money you saved out the other end in your stock, 401k, options, and ownership stakes in any private companies.
We're better off allowing foreigners to invest, with certain restrictions of course.